java - "java.lang.IllegalArgumentException "尝试检索文档数据

Question

这是日志猫:

java.lang.IllegalArgumentException: method group.onservice.onservice.GetData.setTimestamp argument 1 has type java.sql.Timestamp, got java.util.Date at java.lang.reflect.Method.invoke(Native Method) at com.google.android.gms.internal.zzevb$zza.zza(Unknown Source:134) at com.google.android.gms.internal.zzevb.zza(Unknown Source:437) at com.google.android.gms.internal.zzevb.zza(Unknown Source:2) at com.google.firebase.firestore.DocumentSnapshot.toObject(Unknown Source:9) at group.onservice.onservice.ProfileActivity$2.onEvent(ProfileActivity.java:155) at group.onservice.onservice.ProfileActivity$2.onEvent(ProfileActivity.java:146) at com.google.firebase.firestore.zzi.onEvent(Unknown Source:16) at com.google.android.gms.internal.zzevc.zza(Unknown Source:6) at com.google.android.gms.internal.zzevd.run(Unknown Source:6) at android.os.Handler.handleCallback(Handler.java:790) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6494) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:440) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

这是发生错误的代码:

firebaseFirestore.collection("Posts").addSnapshotListener(new EventListener<QuerySnapshot>() {
            @Override
            public void onEvent(QuerySnapshot documentSnapshots, FirebaseFirestoreException e) {

                for (DocumentChange doc : documentSnapshots.getDocumentChanges()) {
                    if (doc.getType() == DocumentChange.Type.ADDED) {
                        AdPost adPost = doc.getDocument().toObject(AdPost.class);
                        ad_list.add(adPost);

                        adRecyclerAdapter.notifyDataSetChanged();
                    }
                }
            }
        });

我实际上不知道如何编程，所以我在一些论坛和视频中搜索了如何做到这一点(我对编程有点陌生)，事实是:我看到每个人都使用相同的代码，并且它对所有人都有效，除了我。因此，没有人报告任何类型的错误。有人可以帮助我理解我的代码有什么问题吗？

PS:指定错误的确切行是这样的:

AdPost adPost = doc.getDocument().toObject(AdPost.class);

AdPost.class:

package group.onservice.onservice;

import java.sql.Timestamp;

public class AdPost {

    String des, image_url, titu, user_id, valo;
    Timestamp timestamp;

    public AdPost() {

    }

    public AdPost(String des, String image_url, String titu, String user_id, String valo, Timestamp timestamp) {
        this.des = des;
        this.image_url = image_url;
        this.titu = titu;
        this.user_id = user_id;
        this.valo = valo;
        this.timestamp = timestamp;
    }

    public String getDes() {
        return des;
    }

    public void setDes(String des) {
        this.des = des;
    }

    public String getImage_url() {
        return image_url;
    }

    public void setImage_url(String image_url) {
        this.image_url = image_url;
    }

    public String getTitu() {
        return titu;
    }

    public void setTitu(String titu) {
        this.titu = titu;
    }

    public String getUser_id() {
        return user_id;
    }

    public void setUser_id(String user_id) {
        this.user_id = user_id;
    }

    public String getValo() {
        return valo;
    }

    public void setValo(String valo) {
        this.valo = valo;
    }

    public Timestamp getTimestamp() {
        return timestamp;
    }

    public void setTimestamp(Timestamp timestamp) {
        this.timestamp = timestamp;
    }

}

Answer 1

代码中的问题是您使用的是 Timestamp 对象而不是 Date 对象作为时间戳。 Timestamp 类不是 supported data type在Firestore。为了解决这个问题，我建议你看看我的答案 post ，我在其中解释了如何使用 Date 类将时间戳存储在 Firebase 实时数据库中。您将看到有两种方法，一种使用模型类，另一种使用 map 和 FieldValue.serverTimestamp()。